Device for closing a tap hole of a metallurgical vessel, in particular a converter, for the purpose of separating a molten metal and slag, having a slag stopper, which is situated outside the vessel, which provides an actuable closure element that can be inserted into a tap hole, leaving an annular gap relative to the wall of the tap hole, and which provides a number of lines, in particular a pressurized-gas line intended for the supply of the closure element.
In the course of commercial development, the system requirements associated with a steel plant have focused increasingly on durability. This development is driven primarily by the enormous progress made in the area of materials technology. A second area on which attention has been concentrated is that of logistics as it relates to internal operations, which has been subject to intense monitoring and optimization. Maintenance and repair work on so-called wearing components, in particular, should have as little effect as possible on the flow of production during operation.
One wearing component of particular importance in steel production is the so-called slag stopper, which is intended to separate metal and slag as the material is poured out of a metallurgical vessel, and is known in the prior art from EP 0010535 A. While the life of a slag stopper was approximately the same as that of a converter, it was possible to remove the slag stopper from the converter without losing too much operating time. However, now that the life of converters, especially the life of linings, has been considerably increased by the use of particularly suitable materials, it is necessary to service the slag stopper on the converter while it is in operation. Removing and servicing the slag stopper known in the prior art are involved and time-consuming.
The object on which the present invention is based is therefore to develop a device for closing a tap hole of a metallurgical vessel, in particular a converter, for the purpose of separating a molten metal and slag, having a slag stopper, which is situated outside the vessel, which provides an actuable closure element that can be inserted into a tap hole, leaving an annular gap relative to the wall of the tap hole, and which provides a number of lines, in particular a pressurized-gas line intended for the supply of the closure element, a device which can be replaced or serviced in a simple and time-saving manner on the converter.
According to the invention, this object is achieved by virtue of the fact that the slag stopper comprises a connecting frame, which carries and fixes the parts of the slag stopper, this connecting frame, for its part, being secured releasably at a connecting point on the metallurgical vessel.
By virtue of the fact that the slag stopper, which includes the closure element itself and a number of lines and means required for correct operation, is fixed on a supporting frame or housing, all the important wearing parts can be replaced simply and with the minimum expenditure of time by replacing the frame or housing with all the parts attached to it, i.e. by replacing one system component. In a particularly advantageous refinement of the invention, all the lines required for the operation of the slag stopper are included in it and are thus also attached to the frame or housing.
According to another feature of the invention, the connecting frame has a, preferably flat, fixing part, by means of which the connecting frame is fixed at the connecting point on the metallurgical vessel.
According to a preferred exemplary embodiment of the subject-matter of the invention, a further, preferably flat, fixing part, in the simplest case a connection plate, is provided at the connection point on the metallurgical vessel, in particular the converter, this fixing part being used to fix the slag stopper on the metallurgical vessel. As well as being used to fix the slag stopper, this fixing part also serves to fix all important lines and connections required for operation of the slag stopper. For simplicity of mounting and removal, the fixing of the slag stopper on the metallurgical vessel is embodied in such a way that it will take a fitter about one hour to replace the slag stopper on the converter, allowing for any technical aids and assuming optimum conditions.
Suitable adjustment of the slag stopper at the connecting point on the metallurgical vessel is particularly important here, this being the only way of mounting it in such a short time. According to another feature of the subject-matter of the invention, this adjustment is accomplished by the formation of one or more hollow spigots on the connections of the lines of the slag stopper and by the formation of one or more sleeves on the connections of the lines at the connecting point on the metallurgical vessel or vice versa. In a preferred embodiment, the connections are each integrated into the fixing parts. According to one feature of the invention, O-rings, preferably made of copper, are used to seal the joints of the mutual connections.
To allow the slag stopper to be fixed releasably on the metallurgical vessel, in particular on the converter, use is preferably made of bolts and particularly preferably of so-called hammer-head bolts, which are distinguished by their ease of handling. One fixing part is advantageously fixed on the corresponding fixing part by means of the said fixing means.
A large number of ways both of adjusting and fixing the slag stopper on the converter apart from those mentioned are conceivable, one example being centring by means of suitable guide pins or similar devices.
According to one feature of the invention, the pressurized-gas line and the actuable closure element are connected to one another by a swivel joint. The swivel joint, preferably a suitably adapted xe2x80x9cswivel rotary jointxe2x80x9d, is distinguished, on the one hand, by its flexibility plus a very small space requirement and high reliability.